Mix the turkey, onion, salt and pepper. Form into 4 patties and cook on your bbq or a grill pan. Meanwhile, toast the bread. Spread the spinach on the bread and put a piece of ham on each sandwich. When the burgers are done, lay the slices of brie on the burgers and cover to let the cheese melt a bit. Then put the burgers on the bread, top with some chutney and serve.